There’s a fair amount of that in the Pacific Northwest; from my (fuzzy) recollection, coastal Oregon and Washington (as Blaine mentioned) would be good places to look.
The fungi and berries (and moss, depending on local climate) will be seasonal, of course. In a wet winter, we even get a fair amount of moss & mushrooms down here in the Bay Area, in among the redwoods.
I’m guessing you’ll need proper rainforest, if you want mushrooms and berries at the same time. Olympic National Park, perhaps?

Oregon, Washington or N. California west of the Cascade mountains. Too dry this time of year. Spring time (March thru June)for the best light and brightest greens. I have lots of haunts that look like that.

I think the coastal ranges of Oregon and Washington would be too dense. The Cascades would probably be a better fit. For Oregon I’ve seen woods that look identical to that in the Santiam Wilderness through to the Deschutes National Forest.

Fly to Seattle, rent a car, and take I-90 East. Go past Snoqualmie Summit and Keechelus Lake, and take the Kachess Lake Road exit. Go South on NF-54, make your way uphill on the logging roads. Lots of terrain like this, complete with mushrooms.

SE Alaska, Oregon and Washington coasts west of the cascades, northern Idaho in the Selkirks for North America. Similar temperate rain forests are found worldwide.

From Wikipedia –

Temperate forests cover a large part of the earth, but temperate rainforests only occur in a few regions around the world. Most of these occur in Oceanic-Moist Climates: the Pacific temperate rain forests in Western North America (Southeastern Alaska to Central California), the Valdivian and Magellanic temperate rainforests of southwestern South America (Southern Chile and adjacent Argentina), pockets of rain forest in northwest Europe (southern Norway to northern Spain and Portugal), temperate rainforests of southeastern Australia (Tasmania and Victoria) and the New Zealand temperate rainforests (South Island’s west coast).

Some areas, however, such as the Rocky Mountains of British Columbia, northern Idaho and northwestern Montana, Rocky Mountain Trench in BC and Montana, and the Russian Far East (Ussuri, Manchuria, Sakhalin) in Asia have more of continental climate but get enough precipitation in both rain and snow to harbor significant pockets of temperate rainforest.

Scattered small pockets of temperate rainforest also exist along the Appalachian Mountains from northern Georgia to New England. The mountainous coniferous forests of the Changbai Mountains bordering China and North Korea are also a good example, containing some of the richest high-elevation coniferous evergreen forests in East Asia.

Colorado has may varied alpine forests. There are the red toadstool mushrooms, forests covered with old man’s beard, streams and waterfalls, aspens and everything in between. it almost looks line Norway in some areas, to the black forest in others, to New Mexico looking desert in others. Then you can drive between areas in about an hour. 1-2 hours from Denver and you can get lost.